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BikeI have this EBS (unknown model please help) rigid steel frame bike.

Due to a recent crash, the fork was bent backwards and a little bit to the right, at the bottom bearing in the headset:

Front View: Front

Left View: Left

Right View: Right

Can this fork get straightened? And if it was straightened would it be safe to use? I think it might be able to get slightly straightened because I know steel is quite flexible compared to other metals and can be bent a lot before cracking or breaking.

I had to put nonfunctional links instead of formatting as images due to lack of reputation.

EDIT There is no paint in some areas because of the brake outer cables rubbing with the frame, NOT because of the crash (it was not there since before the crash).

The front wheel DID absorb some of the shock on impact and was bent and needs straightening+truing or just replacing.

More details about the crash: I was riding in town at 25-30 km/h, when suddenly a parked heavy motorbike comes out of where it was parked. Its rider was busy talking to someone riding with him so he didn't even see if the road was empty. I braked the hardest I could but it was too late, so I crashed into his rear wheel. Fortunately I wasn't hurt. Summary: Crash into the rear wheel of a heavy motor bike at 25-30 km/h

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    For the fork to be that bent, the frame has been stressed well beyond design limits. The head area is a critical stress area and the accidents occur if it fails are never minor. The bottom photo shows paint missing around the head race, needs close inspection by an expert (or just write it off and munted).
    – mattnz
    Commented Jul 22, 2017 at 23:04
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    That fork and frame is toast Commented Jul 22, 2017 at 23:05
  • If it was just the tines bent you'd have a chance of straightening it, but with the steering tube bent where it is the fork is toast (and the bike may be a goner as well). Commented Jul 22, 2017 at 23:31
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    @Criggie I dont think it would help you, because it is a little town in nowhere. Guerrara, Ghardaia, Algeria
    – Tooniis
    Commented Jul 23, 2017 at 12:36
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    You cannot bend that fork back. If you are low on funds you can try another fork. Hopefully you can borrow one to test before you buy. Then look for a used fork.
    – paparazzo
    Commented Jul 23, 2017 at 20:08

2 Answers 2

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I expected the question to be about bent legs/tines on the fork.

That is a bent steerer tube on the fork, which means it was one/both of

  • one heck of an impact
  • exacerbating an existing weakness in the fork.

Impact Did your front wheel get bent? The one in the photos looks fine, so if that's the one then your fork was weak and took all the force. I'd have expected the tube to flat and the wheel rim to go out of round and maybe break some spokes.

Weakness The last photos show its bent just above the bearing race, right on the edge of what gets hot during welding.

My guess is that there was an inherent weakness above the fork crown welds, and this frontal impact has expose the weak metal.

If you attempt to bend it back, you will further weaken the metal either invisibly, or tear the metal in a way you can see.

Todo Your best safest plan is to replace the forks and frame, and keep all the useful parts (like that strong front wheel!)

I'd expect that over time there will be rust developing in a ring around the top and down tubes, about 50mm aft of the head tube. This is another sign of frontal impact.

Just to be clear:

DO NOT RIDE THAT BIKE!

You can remove the fork and inspect the steerer tube with a mark 1 eyeball tool.

  • 5mm hex tool in the top of the quill stem - undo it 2-3 turns only
  • Light tap with a hammer downward to release the wedge
  • Raise the stem out of the steerer and let it dangle
  • Likely you will need a 12" spanner to unbolt the locknut and cone nut and washers
  • Then drop the fork out the bottom of the headtube.
  • But the two bearing races aside too - very likely they will be in cages and not loose bearings.
  • Clean it with a cloth and inspect for damage.

I'd make a decision then to either replace the fork with an undamaged one, or scrap the whole frame and save any useful components.

Remember, if your fork/frame fails while riding, you're going down hard and its going to hurt. There's no time to put on a helmet, you'll be sucking mud before you can react.

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    Yes the front wheel was bent and needs straightening and truing or just replacing. Money would be a problem for me so keeping the frame would be great if possible.
    – Tooniis
    Commented Jul 23, 2017 at 12:02
  • @Tooniis thank you - I'd say the fork is dead/dead. What you want to do now is get a donor bike that has some other fault (ie its got a good fork with the same 1" threadded system, and enough length to get through your head tube) and put all the good stuff on one bike.
    – Criggie
    Commented Jul 23, 2017 at 12:24
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    @Tooniis you could use the old dead fork as a front wheel truing stand, by mounting it in a vise upside-down, and fitting some kind of indicators. I use a couple of cable ties (zip ties) for rough truing of front wheels and I have a separate old fork which has been cold-widened to accept rear wheels.
    – Criggie
    Commented Jul 23, 2017 at 12:26
  • Thats a great Idea for recycling! But finding a donor bike would be a problem, since everyone around here rides broken bikes without caring about their safety (no one even wears a helmet). I guess I will just get a new fork and hope for the best.
    – Tooniis
    Commented Jul 23, 2017 at 12:38
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The quick answer is NO, you can't bend back the fork. Or at least not at a reasonable price.

Your bike looks right knackered. You could maybe find a used fork off a donor bike for free or cheap at a bike coop - but you might put said fork on and find your frame is bent.

I'd say your bike is what we kindly refer to as a said "donor bike." It's brain dead and its best use is to give up its vital organs to a bike that might be able to use them. Given that it looks BSO quality, the parts aren't that valuable but if your next bike is a BSO, you might want a spare drive set, seat, brakes, or rear wheel.

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  • I hope I could keep the frame... I will take it to a shop for inspection, but keep in mind that the shops here are not big shops with everything necessary (including experts to really know if it is safe or not to repair). I edited the question to add more information.
    – Tooniis
    Commented Jul 23, 2017 at 12:21

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